Consolidated Statement of Changes in Equity Statement of Changes in Equity (Parenthetical) (USD $)	3 Months Ended
Mar. 31, 2012
Common Unit Distributions per Unit Cash Paid	$ 0.17

Aggregate distributions paid during the period for each common unit outstanding.

No definition available.

Name:	drlp_CommonUnitDistributionsPerUnitCashPaid
Namespace Prefix:	drlp_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration